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CHAPTER 18 EXPANDED I/O SERIAL INTERFACE
18.5 Operation of Expanded I/O Serial Interface
The expanded I/O serial interface consists of the serial mode control status register
(SMCS) and shift register (SDR). This interface is used for input and output of 8-bit
serial data.
This section describes the operations of the expanded I/O serial interface.
■
Overview of operation for expanded I/O serial interface
Input and output with serial data are individually performed as follows:
❍
Serial data input
By synchronizing with the rising edge of a serial shift clock (external or internal clock), data is
input to the SDR (serial data register) from a serial input pin (Pin SIN1).
The shift direction (data transfer beginning with the MSB or LSB) is specified by the direction
specify bit (BDS) of the serial mode control status register (SMCS).
After data transfer is completed, the operation enters the stop state or data register R/W wait
state as determined by the MODE bit of the serial mode control status register (SMCS). To
change the state from each state to transfer state, to do the following setting.
•
To return from the stop state, write "0" to the STOP bit and write "1" to the STRT bit to set it.
(STOP and STRT can be set simultaneously)
•
To return from the wait state, perform a read or write operation for the data register.
❍
Serial data output
By synchronizing the shift register with the falling edges of a serial shift clock (external or
internal clock), data is output from the serial output pin (SOT1 pin).
Summary of Contents for MB90480 Series
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Page 10: ...vi ...
Page 128: ...106 CHAPTER 4 RESET ...
Page 174: ...152 CHAPTER 6 LOW POWER CONSUMPTION MODE ...
Page 198: ...176 CHAPTER 7 MODE SETTING ...
Page 220: ...198 CHAPTER 9 TIMEBASE TIMER ...
Page 238: ...216 CHAPTER 11 WATCH TIMER ...
Page 280: ...258 CHAPTER 12 16 BIT INPUT OUTPUT TIMER ...
Page 406: ...384 CHAPTER 17 8 10 BIT A D CONVERTER ...
Page 478: ...456 CHAPTER 20 CHIP SELECTION FACILITY ...
Page 494: ...472 CHAPTER 21 ADDRESS MATCH DETECTION FUNCTION ...
Page 498: ...476 CHAPTER 22 ROM MIRROR FUNCTION SELECTION MODULE ...
Page 526: ...504 CHAPTER 23 2M 3M BIT FLASH MEMORY ...
Page 536: ...514 CHAPTER 24 EXAMPLES OF MB90F481B MB90F482B MB90F488B MB90F489B SERIAL PROGRAMMING ...
Page 570: ...548 CHAPTER 25 PWC TIMER ONLY MB90485 SERIES ...
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